1. Field
The present disclosure relates generally to detecting icing conditions and, in particular, to icing conditions for an aircraft. Still more particularly, the present disclosure relates to detecting supercooled water drops, including supercooled large drops (SLD).
2. Background
In aviation, icing on an aircraft may occur when the atmospheric conditions lead to the formation of ice on the surfaces of the aircraft. Further, this ice also may occur within the engine. Ice forming on the surfaces of the aircraft, on inlets of an engine, and other locations are undesirable and potentially unsafe for operating the aircraft.
Icing conditions may occur when drops of supercooled liquid water are present. In these illustrative examples, water is considered to be supercooled when the water is cooled below the stated freezing point for water but is still in a liquid form. Icing conditions may be characterized by the size of the drops, the liquid water content, air temperature, and other parameters. These parameters may affect the rate and extent at which ice forms on an aircraft.
When icing occurs, the aircraft does not operate as desired. For example, ice on the wing of an aircraft will cause the aircraft to stall at a lower angle of attack and have an increased drag.
Aircraft may have mechanisms to prevent icing, remove ice, or some combination thereof to handle these icing conditions. For example, aircraft may include icing detection, prevention, and removal systems. Ice may be removed using deicing fluid, infrared heating, and other suitable mechanisms.
Aircraft may be certified for operating during different types of icing conditions. Some aircraft may be certified to operate in normal icing conditions but not those that include supercooled large drops. Currently used sensors are unable to differentiate between normal and supercooled large drop icing conditions. Therefore, it would be desirable to have a method and apparatus that takes into account one or more of the issues discussed above as well as possibly other issues.